The subject matter disclosed herein relates generally to a system for detecting misconfiguration of a motor drive and, more specifically, to detecting that the selected operating mode of the motor drive does not match the wiring to the motor drive.
As is known to those skilled in the art, motor drives are used to convert a fixed voltage input into a variable amplitude and variable frequency output to control operation of a motor. The voltage input may be a single phase or three phase alternating current (AC) voltage. The motor drive typically converts the AC voltage into a direct current (DC) voltage present on a DC bus and subsequently converts the DC voltage into the variable amplitude and variable frequency output voltage. Conversion of the AC voltage to the DC voltage is performed by a converter and conversion of the DC voltage to the variable amplitude and variable frequency output voltage is performed by an inverter.
It is also known that motor drives or motor drive systems may be arranged in many different configurations. In one application, a single motor may be controlled by a single motor drive in a stand-alone configuration. In other applications, multiple motors may require control. Although individual drives may still be connected in a stand-alone configuration to control multiple motors, the motor drives may also be configured such that the AC inputs and/or the DC busses of the motor drives are connected in a shared AC, shared DC, or shared AC/DC configuration. According to still another option, a first motor may have a drive including a converter having a sufficient power rating to provide power to multiple motors. Each additional motor may have a motor drive with an equal or lower power rating connected in a shared DC bus configuration such that the additional motor drives receive power from the first motor drive. Although the motor drives or motor drive systems may have many different configurations, it is commercially advantageous to provide a single device capable of being configured to operate in each of the configurations.
A motor drive capable of being configured to operate in the various configurations includes terminals providing electrical connections to the converter, DC bus, and inverter within the device. Electrical conductors are connected between the terminals and a power source, another DC bus, or a motor according to the application requirements. In addition, the device includes one or more parameters corresponding to the configuration. A single parameter may be set to identify an operation mode, which, in turn, may be used to set additional parameters. Optionally, multiple parameters may be individually adjusted to configure the device. The parameters may configure, for example, overload warning and/or fault levels. If the parameters are not properly configured, the drive may be subject to alarms and/or faults occurring at levels inconsistent with the wiring or the drive may post alarms and/or faults unrelated to the real problem, namely that the parameters are not configured according to how the drive is wired.
Thus, it would be desirable to provide a system for detecting a difference between the configuration of the parameters of a motor drive and the configuration of the wiring connected to the motor drive.